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为了解万山汞矿区弹琴蛙（Nidirana adenopleura）组织重金属富集特征及其关联，对万山汞矿区典型农田生境内弹琴蛙组织（肝脏、皮肤、股骨、肌肉和趾骨）中铬（Cr）、锰（Mn）、镍（Ni）、铜（Cu）、锌（Zn）、镉（Cd）、铅（Pb）、砷（As）、硒（Se）和汞（Hg）这10种重金属元素的生物富集特征差异进行分析，结合非负矩阵分解分析法识别重金属元素的来源及贡献，并通过灰色关联度分析法分析弹琴蛙组织重金属元素间的关联性。结果表明：重金属元素在万山汞矿区弹琴蛙体内富集程度不同，平均质量分数由大到小依次为Zn、Cu、Mn、Pb、Se、Cr、Hg、Cd、Ni、As；Cu、Se、Cr、Ni、Cd和Hg主要富集在肝脏组织中，Mn、Zn和Pb主要富集在股骨和趾骨组织中，As主要富集在肌肉组织中。基于非负矩阵分解和相关分析，Hg、Cu、Cr、Pb和Se主要源于汞矿开采， As主要来源于农业活动，Mn主要来源于锰矿冶炼，Ni、Zn和Cd来源于多种复合途径。总之，两栖动物趾骨具有较好的生物指示作用，可作为一种非致命性的检测方法，用于动物重金属污染的研究。研究结果可为万山汞矿区环境污染防控和野生动物保护提供科学依据。

概述了平行城市的概念、框架、方法与应用。平行城市是基于 ACP 方法的平行智能在城市领域中的应用。实际城市和与之对应的虚拟空间中的人工城市平行运行、虚实互动，物理空间映射于虚拟空间，人工城市系统描述、预测、引导实际城市系统，虚实闭环，迭代优化，实现智慧城市管理的新模式。

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: The accurate diagnosis of early bone metastases plays an important role in treatment and prognosis. Bone biopsy is the gold standard for the diagnosis of bone metastases, but it is difficult to implement in clinical practice because of its invasive and small specimen size. In recent years, with the continuous development of magnetic resonance imaging technology, quantitative magnetic resonance imaging techniques such as magnetic resonance spectroscopy and based on chemical shift encoded magnetic resonance imaging have been widely used in the diagnosis of bone metastasis. The derived markers include table signal fat fraction and proton density fat fraction. All of them could reflect the bone marrow fat content. At present, the role of bone marrow fat in the development of bone metastases has become a new focus of attention. OBJECTIVE: To review the effect of bone marrow fat on bone metastasis and the quantitative evaluation techniques of magnetic resonance imaging, to summarize and compare the advantages and disadvantages of different magnetic resonance imaging fat quantification techniques in evaluating bone metastasis and their clinical applications. METHODS: The computer was used to search relevant literature in PubMed and CNKI database. Chinese and English search terms were “bone metastases, bone marrow adipocytes, magnetic resonance imaging, quantitative MRI, fat fraction, magnetic resonance spectrum, chemical shift encoding-based water-fat imaging.” A total of 67 relevant articles were obtained according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION: (1) Bone marrow adipocytes can contribute to the occurrence of bone metastasis by secreting a variety of related hormones and cytokines, providing energy for tumor cells, and inducing osteoclast differentiation. (2) Quantitative magnetic resonance imaging can accurately quantify adipose tissue and measure the change of fat content in bone marrow, which is helpful for the diagnosis of bone metastasis. (3) Magnetic resonance spectroscopy can reflect different metabolites through different proton precession frequencies, so it can be used for fat quantification, and is currently used as an auxiliary test to evaluate metastatic fractures. (4) Chemical shift encoding-based water-fat imaging can separate water and fat signals in positive and inverse phases, so as to measure adipose tissue signals, with high sensitivity, specificity and accuracy in differentiating benign and malignant vertebral fractures. [ABSTRACT FROM AUTHOR]

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Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate the effect of cornus officinalis glycosides on apoptosis and oxidative damage of human renal tubular epithelial cells line induced by high glucose by regulating E2-related factor 2 (Nrf2) /heme oxygenase-1 (HO-1) pathway. Methods Human renal tubule epithelial cell line HK-2 was divided into control group (control, 5.5 mmol/L glucose), model group (HG, 30 mmol/L glucose), and total cornus officinalis glycosides groups with low, medium and high dose (L-COG, M-COG, H-COG). After Nrf2 pathway inhibitors were added, HK-2 cells were divided into H-COG group and ML385 group. CCK8 method was used to detect cell activity. Apoptosis was detected by flow cytometry. The expressions of Bcl-2 associated X protein (Bax), B-cell lymphoma/leukemia 2 (Bcl-2), activated caspase3 (cleaved caspase3), Nrf2/HO-1 pathway protein were detected by Western blot. Reactive oxygen species (ROS) content was detected by DCFH-DA, glutathione peroxidase (GSH-Px) activity, superoxide dismutase (SOD) activity, interleukin-6 (IL-6) content and tumor necrosis factor α (TNF-α) content were detected by ELISA. Results Compared with control group, the cell activity, Bcl-2 protein expression, GSH-Px and SOD activity in model group were significantly decreased, and the apoptosis rate, Bax, Nrf2, HO-1 and cleaved caspase3 protein expression, ROS, IL-6 and TNF-α content were significantly increased (P＜0.05). Compared with model group, the cell activity, Bcl-2 protein expression, GSH-Px and SOD activity of L-COG, M-COG, and H-COG were significantly increased. Apoptosis rate, Bax, Nrf2, HO-1, cleave-caspase3 protein expression, ROS, IL-6, TNF-α content were significantly decreased (P＜0.05). Compared with H-COG, the cell activity, Bcl-2 protein expression, GSH-Px and SOD activity in ML385 group were significantly increased. The apoptosis rate, Bax and cleaved caspase3 protein expression, ROS, IL-6, TNF-α content were significantly decreased (P＜0.05). Conclusions The total cornus officinis glucoside may reduce the oxidative stress and inflammatory response of renal tubular epithelial cells induced by high glucose through inhibiting Nrf2/HO-1 pathway and then reduce cell apoptosis. [ABSTRACT FROM AUTHOR]

In order to solve the problem that the sound signal of belt conveyor is seriously disturbed by reverberation and background noise in the acoustic diagnosis, the reasons of reverberation and the composition of sound signal were analyzed, an acoustic signal enhancement method based on super directional beamforming (SBF) and improved singular value decomposition ( ISVD) was proposed. Firstly, the optimal frequency band was selected based on the maximum energy variation to determine the frequency band with more fault information. Then, SBF was used to remove the interference of reverberation on the sound signal, ISVD method was used to reduce the noise of the signal after reverberation, and the envelope spectrum of the signal was analyzed. The fault characteristic frequency measured in practice was compared with the theoretical fault characteristic frequency, and the fault characteristics of the belt conveyor were extracted. Finally, the test was designed, the data were collected, and the data collected from the coal mine site were analyzed and verified by using this method. The method was compared with the weighted prediction error algorithm ( WPE), the linear constrained minimum variance ( LCMV) and the recursive least square method (RLS). The research results show that: comparing with the original signal, the amplitude at the inner circle fault characteristic frequency of 153. 1 Hz and the frequency doubling of 312. 5 Hz in the envelope spectrum of test data processed by SBFISVD method is significantly improved, and the signal-to-noise ratio is significantly increased from - 31. 39 dB to - 25. 4 dB. The sound signal enhancement method based on SBF-ISVD has remarkable effect on removing reverberation and reducing noise, and the bearing fault feature extraction effect is good, which can realize the sound signal enhancement of belt conveyor under complex ambient noise. [ABSTRACT FROM AUTHOR]

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目的　观察关节镜下自体腓骨长肌腱修复膝关节后交叉韧带（Posterior cruciate ligament，PCL）损伤的效 果。方法 20例PCL损伤患者，均在关节镜下行自体腓骨长肌腱双股单束韧带重建术，术后采用膝关节X线片、磁 共振成像（MRI）观察患者膝关节韧带位置及形态，采用抽屉实验、Lachman实验评价患者的膝关节稳定性，术前及 术后末次随访时采用国际膝关节评分委员会（International Knee Documentation Committee，IKDC）评分、膝关节功能 Lysholm评分、美国足踝外科学会（American Orthopedic Foot and Ankle Society，AOFAS）评分判定疗效，观察并记录术 后并发症发生情况。结果　术后X线片检查显示患者骨隧道位置良好，MRI检查显示患者重建韧带信号均匀、无迂 曲，张力良好；术后 20例患者抽屉实验、Lachman实验结果均为阴性。与术前相比，术后末次随访时患者的膝关节 IKDC 评分、Lysholm 评分高（P 均<0. 05), 踝关节 AOFAS 评分差异无统计学意义（P>0. 05). 20 例患者均未出现感 染、血栓、创伤性关节炎等并发症。结论　关节镜下自体腓骨长肌腱双股单束韧带重建术治疗PCL损伤效果较好， 可有效恢复膝关节稳定性，不影响踝关节的功能，且并发症少。 [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of treatment with nicorandil after Percutaneous Coronary Intervention (PCI) in patients with Acute Coronary Syndrome (ACS) on inflammation-related markers, and to assess its effects on vascular endothelial function. Methods　Sixty-six ACS patients who underwent PCI in the Department of Cardiovascular Medicine of the Second Affiliated Hospital of Dalian Medical University from August 2022 to January 2023 were used as the study sample, and were divided into the control group and the experimental group according to the method of completely randomized design, with 33 cases in each group. The control group was treated with conventional therapy, and the experimental group was treated with nicorandil. Inflammatory indexes, homocysteine ( Hcy) and adverse reactions in serum were compared between the two groups. Results　After nicorandil treatment, the levels of postoperative inflammation-related factors in the control group were higher than that in the experimental group, and the difference was statistically significant (P < 0.05) ; The levels of Hcy after nicorandil treatment were lower than that in the control group, and the difference was statistically significant (P < 0.05) ; and the rate of adverse reactions in the experimental group was higher than that in the control group, and there was no statistical difference (P > 0.05). Conclusion　Nicorandil application in elderly ACS patients after PCI has a definite efficacy, can optimize the vascular-related inflammatory indexes, reduce homocysteine levels to improve coronary vascular endothelial function, and is suitable for further promotion. [ABSTRACT FROM AUTHOR]

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The productivity of ruminants is mainly driven by rumen microorganisms, including functional microbial communities such as bacteria, methanogens, fungi, and protozoa. Rumen microorganisms can decompose and ferment plant-based feed to produce nutrients such as volatile fatty acids, microbial proteins, and vitamins. From the early stages of animal life to each important node of life, the rumen microbial community undergoes drastic changes. At present, early regulation of rumen microbiota in ruminants is one of the hot topics in the field of animal husbandry research. Therefore, understanding the colonization status of rumen microorganisms is of great significance for the healthy of animal bodies. The paper reviewed the common microbial flora in rumen, its main functions and colonization process, in order to understand the rumen microflora of ruminants and provide reference for further research. [ABSTRACT FROM AUTHOR]

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